1. Field of the Invention
The invention relates to knotted mesh structures, and to methods and apparatus for the manufacture thereof.
2. Description of the Prior Art
Mesh structures in the form of nets are well known which are constructed of flexible members knotted together. The conventional form of such a net is shown diagrammatically in FIG. 1 of the accompanying drawings, where the locus of a typical member as it passes from knotted junction to knotted junction is shown by arrows 1; the locus of a neighbouring member is shown by arrows 2. Such a structure is unsuitable if, for instance, it is required that the member portions lying in one direction should have different properties from those lying in the transverse direction.
A suitable structure meeting this requirement is shown in FIG. 2 of the accompanying drawings, where the loci of two typical members are shown respectively by the arrows 3 and 4 and the member 3 may have different properties from the member 4. Such a difference in properties is, for instance, required for electrified fence netting for the control of animals where it is desirable that the horizontal members are electrical conductors and the vertical members electrical insulators. It may also be desirable that the vertical members are more rigid than the horizontal members.
It has previously been proposed in UK Pat. No. 1,110,793 to construct such a net by surrounding the members in the region of each junction by a mass of moulded thermoplastics material, as an alternative to knotting. Such a structure has disadvantages: if the members are sensitive to heat they are liable to be weakened by the heat evolved by the moulding process; members are liable to slip through the moulded junctions when loaded unless the masses of moulded material are large; and the rate of production is limited by the inherent slowness of the moulding process.